Squeak/chirp from engine when under load and low RPM only

tom9192 · 10-16-2017, 01:12 PM

There's a squeak/chirp coming from the engine and I can't figure it out for the life of me. It is easily reproducible when the car is in gear(any gear), RPM around 1500-2500, and accelerating slightly. It is a constant chirp until I remove my foot from the pedal and halt the acceleration, or oddly if I put my foot all the way down it's not there.

I've replaced the drive belt, tensioner pulley, and idler pulley, but that didn't help.

When I changed my coolant ~8k miles ago I did notice it was slightly more blackish then in the past. The noise started about 2k miles ago.

2006 325i w/ 132k miles on it

Thanks!

tom9192 · 10-17-2017, 07:22 PM

I was thinking it may be a bad head gasket. Does anyone know if this would cause a "compression chirp"?

Also, just doing an oil change now and oil looks good to me, although it's a bit foamy. This look normal to you guys? (One of the symptoms of a bad gasket is coolant in oil)

JuniorB · 10-17-2017, 08:27 PM

Do a oil sample, it's only way to verify what's in your oil. And what the hell is a compression chirp???????

JuniorB · 10-17-2017, 08:32 PM

Btw, that oil looks horrible, put some in a clear glass and wait till it settles. You will see any separation of different fluids if you have any. Do not do anymore 8k oil changes till you know what going on internally. Use some decent lol.

hassmaschine · 10-18-2017, 12:08 AM

Could be the OFHG. I dout it's the head gasket - those rarely fail in reality. The OFH can allow the mixture of coolant and oil, though. I agree that oil looks nasty..

tom9192 · 10-18-2017, 06:31 AM

I heard the term compression chirp somewhere online- can only assume it's air leaking out of the combustion chamber due to a bad head gasket. Sounded plausible when I read it.

This oil change was after 9k miles and this is oem bmw oil. I'll have to send a sample in next time as I mixed the oil with other fluids already.

I'll swap out the OFHG- just did the VCG as that was leaking so very possible the OFH is bad too.

frenchi · 10-18-2017, 07:40 AM

A small crack or a broken bolt on the valve cover will do that as well as crankcase ventilation membrane.

tom9192 · 10-25-2017, 03:15 PM

Oddly enough after I changed the oil, I no longer hear the squeak.

10-16-2017, 01:12 PM	#1
tom9192 Private 23 Rep 78 Posts Drives: 325i '06 Join Date: Oct 2017 Location: North Carolina iTrader: (0)	Squeak/chirp from engine when under load and low RPM only There's a squeak/chirp coming from the engine and I can't figure it out for the life of me. It is easily reproducible when the car is in gear(any gear), RPM around 1500-2500, and accelerating slightly. It is a constant chirp until I remove my foot from the pedal and halt the acceleration, or oddly if I put my foot all the way down it's not there. I've replaced the drive belt, tensioner pulley, and idler pulley, but that didn't help. When I changed my coolant ~8k miles ago I did notice it was slightly more blackish then in the past. The noise started about 2k miles ago. 2006 325i w/ 132k miles on it Thanks!
	Appreciate 0 Tweet Quote

10-17-2017, 07:22 PM	#2
tom9192 Private 23 Rep 78 Posts Drives: 325i '06 Join Date: Oct 2017 Location: North Carolina iTrader: (0)	I was thinking it may be a bad head gasket. Does anyone know if this would cause a "compression chirp"? Also, just doing an oil change now and oil looks good to me, although it's a bit foamy. This look normal to you guys? (One of the symptoms of a bad gasket is coolant in oil) Attached Images
	Appreciate 0 Quote

10-17-2017, 08:27 PM	#3
JuniorB Major 185 Rep 1,017 Posts Drives: 07 e60 525 N54 Join Date: Mar 2016 Location: Rhode Island iTrader: (0)	Do a oil sample, it's only way to verify what's in your oil. And what the hell is a compression chirp???????
	Appreciate 0 Quote

10-17-2017, 08:32 PM	#4
JuniorB Major 185 Rep 1,017 Posts Drives: 07 e60 525 N54 Join Date: Mar 2016 Location: Rhode Island iTrader: (0)	Btw, that oil looks horrible, put some in a clear glass and wait till it settles. You will see any separation of different fluids if you have any. Do not do anymore 8k oil changes till you know what going on internally. Use some decent lol.
	Appreciate 0 Quote

10-18-2017, 12:08 AM	#5
hassmaschine Major General 3966 Rep 7,215 Posts Drives: "NBO" 330i Join Date: Jun 2014 Location: earth iTrader: (0)	Could be the OFHG. I dout it's the head gasket - those rarely fail in reality. The OFH can allow the mixture of coolant and oil, though. I agree that oil looks nasty..
	Appreciate 0 Quote

10-18-2017, 06:31 AM	#6
tom9192 Private 23 Rep 78 Posts Drives: 325i '06 Join Date: Oct 2017 Location: North Carolina iTrader: (0)	I heard the term compression chirp somewhere online- can only assume it's air leaking out of the combustion chamber due to a bad head gasket. Sounded plausible when I read it. This oil change was after 9k miles and this is oem bmw oil. I'll have to send a sample in next time as I mixed the oil with other fluids already. I'll swap out the OFHG- just did the VCG as that was leaking so very possible the OFH is bad too.
	Appreciate 0 Quote

10-18-2017, 07:40 AM	#7
frenchi Lieutenant 89 Rep 452 Posts Drives: F30 340i M Performance Join Date: Nov 2008 Location: France iTrader: (11)	A small crack or a broken bolt on the valve cover will do that as well as crankcase ventilation membrane.
	Appreciate 0 Quote

10-25-2017, 03:15 PM	#8
tom9192 Private 23 Rep 78 Posts Drives: 325i '06 Join Date: Oct 2017 Location: North Carolina iTrader: (0)	Oddly enough after I changed the oil, I no longer hear the squeak.
	Appreciate 0 Quote